Spermine binding to liver mitochondria deenergized by ruthenium red plus either FCCP or antimycin A.
Thermodynamic analysis of spermine binding to mitochondria treated with ruthenium red and deenergized with either FCCP or antimycin A confirms the presence of two polyamine binding sites, S1 and S2, both with monocoordination, as previously observed in energized mitochondria [Dalla Via et al., Biochim. Biophys. Acta 1284 (1996) 247-252]. Both sites undergo a marked change in binding capacity and binding affinity upon mitochondrial deenergization. This change is most likely responsible for the incomplete or delayed spermine-mediated inhibition of the permeability transition induced in deenergized mitochondria.
Dalla Via
L
L
Dipartimento di Scienze Farmaceutiche, Università di Padova, Padua, Italy.
Di Noto
V
V
Toninello
A
A
D000818:Animals; D000968:Antimycin A / Q000494:pharmacology*; D001665:Binding Sites; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone / Q000494:pharmacology*; D004734:Energy Metabolism / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D008933:Mitochondrial Swelling / Q000187:drug effects; D011485:Protein Binding / Q000187:drug effects; D051381:Rats; D012430:Ruthenium Red / Q000494:pharmacology; D013096:Spermine / Q000378:metabolism*; D013816:Thermodynamics
D012430:Ruthenium Red; D013096:Spermine; D002259:Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone; D000968:Antimycin A